Ultraviolet (UV) lights encompass lights having wavelengths of 4 to 400 nanometers. The longer wavelengths of the ultraviolet light spectrum are called black light, which have wavelengths slightly shorter than those that are normally visible and is generally safe for human viewing. Black light appears as a deep blue light because only a portion of the light has long enough wavelengths to be visible to human. For the purpose of this invention, blue black lights are simply called black light. An example of a shorter wavelength in the ultraviolet light spectrum is germicidal ultraviolet light that emits a much shorter wavelength that is dangerous to human skin and eyes.
The barely visible and invisible black light energizes fluorescent and/or phosphorescent pigments which then re-emits the light in visible colors. This results in the object appearing to have an independent glow as if internally lit. Black lights have been used as a source of illumination in theatrical productions, amusement park rides and home use for illuminating art covered with fluorescent and/or phosphorescent paint, and for general atmospheric effects for numerous years.
Traditionally, a black light source is generally a tube, similar to a fluorescent tube that produces white light, of a certain length. Traditional black light source is not conveniently portable due to the size and the need of either alternating current or large voltage direct current. While black light has been used to illuminate all sorts of fluorescent or phosphorescent objects, black light as a portable device has been used only more recently. Using light emitting diodes (LEDs) that can produce UV black lights (generally known as UV LED, portable black light devices are developed. UV LEDs are similarly sized as typical prior art LEDs and can be powered by direct current such as batteries.
The inventor's prior “Portable Black Light Device” using UV LEDs is disclosed in U.S. Pat. No. 6,969,178. The ‘178 patent is a head gear having UV LEDs directed towards and illuminate the wearer's face or the upper portion of the head gear having fluorescent or phosphorescent elements thereon.
Other head gears that provide entertaining values are disclosed in U.S. Pat. Nos. D448,527, D287,061, D283,749, and D283,268. These prior art head gears disclose holders attached to the head gears for receiving beverage cans and straws are incorporated into the head gear for insertion into the beverage cans such that a wearer can consume the beverage while the cans are held in the holders.